<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      "use strict";
      const user = {
        name: "user",
      };
      const admin = {
        name: "admin",
      };
      function say() {
        console.log("say:", this);
      }

      user.sayHello = say;
      admin.sayHello = say;

      say(); // undefind
      user.sayHello(); // user
      admin.sayHello(); // admin
    </script>
  </body>
</html>
